Purpose This study investigated the effects of postural control training using a visual scanning task on postural alignment, balance, and gait in children with spastic diplegia. Methods Eighteen children with spastic diplegia were assigned to a study group (n=9) or control group (n=9) using matchedpair randomization based on age and functional level. Both groups trained for 30 minutes per session, three times weekly, for five weeks. The study group performed postural control training using a visual scanning task, whereas the control group received conventional weight transfer training. Outcomes included the supplementary craniovertebral angle, lumbar lordosis angle, Trunk Control Measurement Scale, and gait parameters. Results In the study group, the supplementary craniovertebral angle, lumbar lordosis angle, and gait symmetry indices significantly decreased, whereas trunk control scores significantly increased. Lower supplementary craniovertebral angles indicated improved head alignment, and lower symmetry index values indicated greater gait symmetry. In the control group, lumbar lordosis angle, gait velocity, and average stride length significantly decreased, whereas static sitting balance, dynamic reaching, total trunk control score, and step length symmetry index significantly improved. Betweengroup differences were significant for static sitting balance, selective movement control, dynamic reaching, total trunk control score, and step length symmetry index. Conclusion Postural control training using a visual scanning task may improve postural alignment, trunk control, and gait symmetry in children with spastic diplegia. Although gait velocity and average stride length decreased, gait changes should be interpreted as qualitative changes in gait patterns rather than speed alone.